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1st place in the Seminole Hard Rock $3,500 Main Event 2016 for $564,227
Patrick “pmahoney22” Mahoney - Boss Ranger PRO

Important Note

Boss Ranger was specically designed for advanced players as a way to practice, test and ultimately improve the accuracy of their reads (ranges). Before using Boss Ranger, we recommend that players have at least a general understanding of the following concepts:

  • Hand Ranges
  • Pot Odds
  • Expected Value (EV)
  • Hand Equity

Poker is ranges

Poker is complex because we don’t know what the hell our opponent’s cards are! All we know for sure is that they have 1 combination of a possible 1,326 (or 1,225 if you discount your own 2 cards). In his book, The Theory of Poker, David Sklansky said,

"If everybody's cards were showing at all times, there would always be a precise, mathematically correct play for each player. Any player who deviated from his correct play would be reducing his mathematical expectation and increasing the expectation of his opponents. Of course, if all cards were exposed at all times, there wouldn't be a game of poker."

He went on to state that the Fundamental Theory of Poker is:

"Every time you play a hand differently from the way you would have played it if you could see all your opponents' cards, they gain; and every time you play your hand the same way you would have played it if you could see all their cards, they lose."

So, if the aim of poker is to play hands the same way you would if you knew what your opponents cards were, what skill should players focus on improving? Logically, a players primary focus should be on improving their ability to consistently put their opponents on the most narrow and accurate range possible.

Feel free to quote me,

"The more accurate our range, the more we gain."

It doesn’t matter what style you’re trying to play (GTO, exploitative or a mix) you should always be aiming to put your opponent on the narrowest possible range that still contains their actual hand combo. Here is a list of the calculations and decisions that require you to put your opponents on a range:

  • Equity calculations
  • Pot odds calculations
  • Every decision to check
  • Every decision to call
  • Every decision to bet
  • Every decision to raise
  • Every decision to fold

You get the point, everything you do requires ranges. However, not all ranges are equal. Any player can learn to make correct calculations based on ranges but it is the accuracy of the range that is the key variable and ultimately the factor that separates the sharks from the fish. Meaning, just because you assign your opponent on a range it doesn’t mean that your calculations and decisions will be good, optimal or in reality +EV. Everything depends on the accuracy of the ranges you assigned.

Here are 3 players that were given the same hand to analyze and asked to decide what they would do on the river.

The community cards:

The Hero had 2 pair with the hand combo:

On the river, the villain bet 50% of the pot.


Based on Bobby’s reads he assigned the villain this betting range:

Bobby’s range has 17.28% equity meaning his hand would only win the pot 17.28% of the time if he called

Bobby worked out that the pot odds to call were 3:1, so in order to make the call profitable (+EV) he needs at least 25% equity. Based on his range he only has 17.28% equity which isn’t enough to call.


Based on Steve’s reads he assigned the villain this betting range:

Steve’s range has 48.37% equity meaning his hand would win the pot 48.37% of the time if he called

Steve worked out that the pot odds to call were 3:1, so in order to make the call profitable (+EV) he needs at least 25% equity. Based on his range he has 48.37% equity which is more than enough to call.


Based on Bill’s reads he assigned the villain this betting range:

Bill also assigned the villain an all-in calling range of:

Phil’s all-in calling range shows that the hero will only call with 31.34% of the hands in his betting range. That means 68.66% of the time he will fold to an all-in raise.


The three players all made correct calculations but each player made a different play. What happened was that the players all drew different conclusions from the same information and assigned different ranges to the villain.

In summary, players that (on average) assign ranges that are too narrow, will be checking and folding more often that they should be. Conversely, players that (on average) assign ranges that are too wide, will be betting, calling and raising more often than they should be. The only way to consistently calculate and make optimal plays, is to consistently calculate using accurate ranges.

Okay, that makes sense, but how do we work out whether our ranges are (on average) accurate or not? Keep reading...


Boss Ranger is the simplest and most effective way to test and improve the accuracy of a players reads. It was designed by a group of profitable players and was built specifically as a reliable way to see how often the ranges they assign to players were accurate (included the villains actual hand). At the same time, it allows players to compare the ranges they selected with other players.

It’s important to know that Boss Ranger is not a poker training site, it is a poker training tool, meaning we do not suggest how players should think or which decisions they should make. Instead, Boss Ranger allows players to practice thinking for themselves by analysing real money poker hands (from Pokerstars). The process is simple:

Analyze a Hand
Make a Read
Select a Range

Boss Ranger utilises a ranging concept known as, The Funnel Principle, which forces players to assign a pre-flop range and then increasingly eliminate hands combos on future betting rounds.


There are plenty of great books and training sites that have professional players explaining the factors they consider when making reads and the rationale behind their decisions. These are useful as a way to learn the types of factors that you may also want to consider during hands. However, when you play poker you won’t have a pro telling you what to do; you will have to make your own reads and decisions.

Practice is a necessary part of mastering any complex skill. Prior to Boss Ranger, the only way to practice making reads was to actually play poker for real money. In real money games, generally only between 85-90% of hands don’t go to showdown. This stops players from learning from their opponents true tendencies and means they only gain validated learning in 10-15% of the hands they play. Boss Ranger solves this problem and also has a few other useful features for players. Here is a comparison between playing poker and using Boss Ranger:

Playing Poker
Boss Rangers
Make reads on opponents in real money poker handsYesYes
See your opponents actual cards & gain validated learningonly ≈ 15%100%
See if your range was literally accurateNoYes
See how your Read Accuracy™ compares to other playersNoYes
Forced range based thinkingNoYes
Forced Funnel Principle adoptionNoYes
Track your improvement with Read Accuracy™ averageNoYes